1. Field of the Invention
The present invention relates to image display devices and method, and more particularly, to a display device and method to optimize a response time of the display device by compensating image data using look-up tables of compensation data in association with temperature variation and frequency variation of the display device.
2. Description of the Related Art
Liquid crystal display (LCD) devices generally have merits such as high and uniform luminance, high efficiency, long lifetime, thin thickness, light weight, low cost and so on. The LCD devices with such merits have widely used for various types of electronic goods such as desk-top computers, notebook computers, automotive navigation systems, television sets, etc.
In particular, when an LCD device is employed in a television set, a response time of the LCD device is an important factor in displaying, especially, moving images.
In other words, compared to other electronic goods, such as computers, mostly displaying standing images, televisions usually display more moving images. Since the display quality of moving images is affected by the response time of an LCD device employed in a television set, there have been developments to improve the response time of LCD devices.
The response time of conventional LCD devices for changing a gray to another gray is in the range from about 10 ms to about 16 ms. Since the vertical frequency of a television receiver set according to national television system committee (NTSC) is 60 Hz, a time period of one (1) frame is about 16.7 ms. Thus, it has been desired to improve the response time of LCD devices to meet such a standard.
The response time of an LCD device is dependent on ambient temperature of the LCD device. A dielectric constant of liquid crystal in an LCD device varies depending on the ambient temperature of the LCD device. A dielectric constant of liquid crystal aligned parallel with a substrate and a dielectric constant of liquid crystal aligned perpendicular to the substrate vary in accordance with variation of the ambient temperature. The difference between the dielectric constant of the liquid crystal aligned parallel with the substrate and that of the liquid crystal aligned perpendicular to the substrate also varies in accordance with variation of the ambient temperature. This is because the order parameter of the liquid crystal varies in accordance with variation of the ambient temperature.
In addition to the ambient temperature, the response time of an LCD device also varies in association with a vertical synchronizing signal of the LCD device. In case that the frequency of a vertical synchronizing signal of an LCD device is changed, the response time of the LCD device is also affected by the variation of the frequency of the vertical synchronizing signal.
Therefore, a need exists for a display system which provides quality images by improving the response time of a display device. Further, it will be advantageous to provide a method of improving the response time of a display device in association with an ambient temperature of the display device and a frequency of a vertical synchronizing signal of the display device.